Offset belted roof ventilator



Jan. 9, 1962 L. .1. JENN ETAL OFFSET BELTED ROOF VENTILATOR 2Sheets-Shea?I 1 Filed Nov. 25, 1959 |J| .1 mm| Jan. 9, 1962 Filed Nov.23, 1959 L. J. JENN ETAL OFFSET BELTED ROOF YENTILATOR 2 Sheets-Sheet 2NHIIIIII 52 7k INVENToRs.

United States Patent O 3,016,003 OFFSET BELTED ROOF VENTILATOR Louisl.Jenn and William E. Morrison, Indianapolis, Ind.,

asslgnors to Jenn Air Products Company, Inc., Indianapolis, Ind., acorporation Filed Nov. 23, 1959, Ser. No. 854,969 6 Claims. (Cl. 98-43)I 'I'his invention relates generally to roof ventilator or air dischargeassemblies and in particular to a ventilator assembly in which the drivemeans is offset and removed from the main hood or cover.

In assemblies of the type referred to it is desirable to locate thedrive motor out of the air stream. 'In the past this has beenaccomplished by forming the main hood or cover so as to provide a recessout of the air stream which accommodates the drive motor. With the motorlocated inside the hood which must be weather-tight, whenever the motoror other components of the drive assembly must be serviced, access tothe motor can be had only by disassembling this weatherproof enclosure.The arrangement of the present invention provides a location for themotor which is exterior of the weather-tight hood and is easilyaccessible for service or replacement.

The primary object of the present invention is to provide a Ventilatorassembly in which the dn've motor is supported exteriorly' of the fanhood and laterally adjacent to the impeller thereby providing easyaccess to the drive component and a relatively low over-all height forthe complete assembly.

A further object of the present invention is to provide an assembly ofthe type referred to in which the complete assembly may be hingedlymounted to a roof curb structure with the drive motor being disposedoutwardly` of the axis of the hinged mounting whereby it acts as acounterweight when the assembly is tilted.

A further object of the present invention is to provide a drive motormounting which does not require the usual belt tighteningV adjustmentafter the initial run-in period.

A further object of the present invention is to provide an assembly ofthe type referred to in which the driven shaft and drive motor lareseparated to provide a relatively long center distance therebysubstantially increasing belt life.

The full nature of the invention will be understood from theaccompanying drawings and the following description and claims:

PIG. l is a perspective view of the ventilator assembly holvving themotor and transmission means cover tilted FIG. 2 is a side sectionalview of the assembly.

FIG. 3 is a top plan view of the drive motor and its mounting means.

FIG. 4 is a side sectional view of a modified form of the assemblyadapted to incorporate an `axial ilow fan rather than a centrifugal-typeimpeller.

FlG. 5 is a side sectional view of the assembly of `FIG. 2 but modifiedto incorporate an impeller'bearing which differs from that of FIG. 2.

Referring initially to FIG. l, the assembly includes a generallyrectangular frame member which is formed to provide an air inletaperture 11. A concave-convex hood 12, which may be formed of spunaluminum, is disposed in spaced, overlying relation to the inletaperture 11 with its concave side facing the aperture. EX- tendingvertically within the hood and coaxially therewith is a shaft 13, theupper end of which extends exteriorly of the hood and carries a multipleV-belt pulley 14. Spaced, L-shaped members 16 are disposed exteriorly ofthe hood and have their radiallyextending legs secured to the hoodadjacent its center and have their Patented Jan. 9, 1962 rice verticallegs rigidly attached to the hood adjacent its peripheral margin. Bolts17 and 18, shown in FIG. 2, may be utilized as attaching means for themembers 16. Supported by the vertical legs of the members 16 is a drivemotor 19 whose shaft carries a pulley 21. Rotary motion of the motorshaft is transferred between the pulleys 21 and 14 by means of amultiple V-belt 22. A cover 23 for the motor and transmission means ispivotally supported at the lower marginal area of the hood 12. The cover23 is shown in FIG. l positioned so as to expose the motor. yInoperating position, it will be understood the cover will be rotatedcounterclockwise from its position of FIG. l so as to enclose the motor,belt and pulleys.

Referring now to FIG. 2, the frame member 10 is shown as being supportedon a curb structure 15 which extends vertically from a roof or otherhorizontal surface and borders the outlet end of a discharge duct. 'I'hecurb structure 15 may be encased within a ashing 24. To install theassembly of the present invention, the ashing may be cut away asindicated at 26 and two spaced, L-shaped brackets 27 may be secured tothe curb structure 15 by such means as lag bolts 23. The frame member 10is somewhat longer than the corresponding dimension of the curbstructure so that it overlies and encloses the members 27. The curbstructure is apertured adjacent the brackets 27 to receive pintles orhinge pins 29 which yalso extend through registering apertures in theadjacent brackets 27. It will be understood that the mounting for theframe member thus provided permits the frame and the remaining portionof the assembly supported thereon to be pivoted clockwise about thepintles Z9, permitting access to the discharge end of the duct and tothe louvers (not shown) which are conventionally disposed at thedischarge end ofthe duct. n

The frame member is formed to provide a generally vertically extendingportion 31 and a horizontally extending portion 32 terminating in anupwardly directed lip 33. The lip portion 33 defines the air inletaperture to the assembly and directs air smoothly into thecentrifugal-type impeller indicated generally at 34. The impeller is ofconventional type and is locked for rotation to the shaftr13 by means ofthe hub 36.

The shaft 13 is supported at its lower end by means.

of the bearing assembly 37 which includes a support plate 38 mounted bymeans of bolts '39 upon tabs 41. The tabs 41 extend sidewardly fromspaced, radially extending support members 42, the outer ends of thesupport members being attached by means of bolts 43 to the portions 31of the frame member 10. Also supported by the bolts 43 is a tubular,vertically-extending element 44 whoseupper end is formed to provide anoutwardlly hanged-lip '46; This tubular element 44 extends adjacent thelower end of the impeller and provides an Yincreased air handlingeciency for the assembly.

The upper end of the shaft 13 extends through an aperture in the upperend of the hood and is supported for rotation by means of an upperbearing assembly 47. The bearingassernbly 47 is supported by means ofbolts 48 which extend through the hood andrthrough a stiffening plate 49secured to the upper end of the hood by means of bolts or screws 51. y

vA wire grill 52 Lof substantial rigidity extends from the frame member10, being secured thereto by means of bolts 43. The outer margin of thegrill is formed so as to permit attachment thereof to the hoodv by meansof the lower series of bolts 18. The grill 52 thus serves to support thehood 12 and functions as a guard which prevents the entry of birds intothe assembly. The righthand portion (as viewed in FIG. 2) of the hood isreinforced by means of tw-o brace members 53 which extend from the framemember 10 and are secured to the hood by means of the upper series ofbolts 18. This reinforced portion of the hood has attached thereto thelower ends of the vertical legs of the members 16. A hinge mountingmeans, indicated generally at 54 in FIG. 2, serves to support invertical position the motor 19. The marginal edge of the hood adjacentthe motor has rigidly secured thereto a pair of brackets S6 havingoutwardly extending ears 57 and the adjacent sides of the cover 23A areprovided with registering apertures which accommodate a pintle Vor pivotpin S. As previously mentioned, the cover 23 Yis thus supported so thatit may be moved into and out of `its motorV and transmission meansenclosing position. Y

Y Referring now to FlG. 3, the mounting means 54 for the motor 19 willbe described in detail. This mounting 'means includes a'hinge plate 61which is weldwith horizontally kelongated slots 64 through which themotor mounting bolts extend, the slots permitting limited adjustabilityof the position of the motor in a horizontal Y plane. `Extending yfromone 'face of the plate 63 is a pin 66. TheV pin 66 extends freelythrough any elongated slot 67 in the plate 61 and has a headV 66a whichdefines the maximum separation ofthe plates 61 and 63. A compressionspring 68 extends between the plates 63 and 61 and axially accommodatesthe pin 66. From the foregoing it will be evident that the spring 68serves to urge the motor 19 clockwise about the pivot 62 and` serves tomaintain tension on the belt 22. rThis arrangement eliminates thenecessity for adjustment of belt tension subsequent to the run-in.

In operation, with the motor 19 energized, the impeller 34 will draw airthrough the apertureV deined by the lip 33 and will direct this airdownwardly through the space separating theV hood v12 and the framemember 10. yShould access be required to the motor or motiontransmission means, the cover 23 may be moved to its position of FIG. l.Should access be required to the discharge end of the duct, the entireassembly may be pivoted clockwise around the pivot 29.- Such move- Vmentof the assembly is facilitated by the arrangement whereby the motor 19is supported outboard of the pivot 29. The substantial weight of themotor thus acts as a counterweight, aiding the clockwise pivotalmovement of the entire assembly.

The motor in the assembly of the present invention is supportedsubstantially in the same plane as the impeller to reduce the overallheight and the motor is mounted exteriorly of the hood 12 whereby the-motor compartment is not indented intothe air discharge space. The

motor mounting means is such that, forV ease in handlingV of Itheassembly prior to installation and Afor preventing damage to the unit inshipment, the motor 19, together with plate 63, can be removed afterinspection and test by merely pulling the hinge pin y62 and vremovingthe pin 66. The motor and attached plate may then be securely fastenedt-o the shipping crate. The assembly further lends itself to easyhoisting into mounting position with the off-center hoisting motorweight removed. The components of the drive system are mounted on thehood 12 which is supported on the base frame by the welded wire grill52. The naturalV or resonant vibrational frequency of the 'substantialweight supported on the wire grill is low enough to be below thekoperating 4speeds of the unit.

The guard grill is, however, exible enough to dampen the frequenciesgenerated by operation of the drive unit and prevents them from reachingthe base frame and thus prevents them from being transmitted to theinterior of the building. The bearing arrangement provides a relativelylarge distance between the limpeller bearings, thus keeping vibration ofthe driven memberV and Ibearing wear to a minimum. The relatively longcenter distance between the shaft provides a prolonged belt life. Thehinge cover for the motor and transmission means provides aweather-proof shield for these element-s and yet permits easy accessthereto.

Referring to FIG. 5, a modified form of the assembly will be described.ln FIG. 5, parts which are identical to those of FlG. 2 are given thesame reference numerals. In the modified form of FIGS Vthe bearings forthe impeller shaft 13 are supported or suspended entirely from the hood12.

The bearino structure comprises Alocking collars 81 and 82 Vrigidlysecured to the shaft 13. A tubular element 83, carrying at its ends themembers 8'4 and 86, has a hanged upper end 87 which is secured by meansof screws 88 to an annular plate 89. The plate 89 is rigidly secured bymeans of screws 51 yto ythe upper, central face of the hood 12. Theshaft 13 extends beyond the end of the bearing assembly and has keyedthereto a hub 91 which carries the centrifugal impeller 34. n Theconstruction of FIG. 5 thus eliminates the lower bearing assembly 37 ofFIG. 2 and utilizes a shorter shaft 13. Yln the FIG. 5 construction theupper and lower bearings are rigidly supported by a unitary Velement 83thereby reducing or eliminating any tendency for the shaft 13 to whip oroscillate ofi the vertical.

Referring now to FIG. 4, -a modified form of the assembly will now bedescribed. 1n FIG. 4, parts which are similar to those shown in FiG. 2are given the same reference numerals but with the ,suixfb In this for-mthe lowerV portion of the assembly is the same as that shown in FIG. 2,however, the air moving means takes the form of an axial discharge typefan which includes blades 71 supported on a spider 72 carried by a hub73. VThe hub 73 is rlocked to la central, vertical shaft 74. The lowerend of the yshaft is journaled in a bearing assembly 76 carried by thehorizontal portion 77 of a frusto-conical -mem- -ber 78. The upper endof the shaft 74 is journaled in a bearing assembly 79supported on theupper end of the hood 12b.. The member 78 is -supported at its base byand depends from the hood 12b, being attached thereto by means of bolts81. 'Ihe portions of the guard grill 52b which extend radially outwardare provided with eyelets 82 to which are rigidly secured an annular,arcuate directional vane 83. The vane 83 serves to split the airdischarge of the fan blades between the member '44b and the hood 12b.The motor 19b, pulleys 2lb and 14b, together with belt 22h form themotor drive tand transmission means whic'h are shielded bythe pivotallymovable cover 23b. Y

The structure shown in FIG. 4 incorporates the advantages mentioned withreference to the structure of FIG. 2. ln the -form ofthe structure shown.in FIG. 4, the lower :bearing 76 journaling the fan shaft 74 issupported by the conical member 78, the entire support for the shaftVthereby depending from the upper end of the hood 12b.

While the invention has been disclosed and described in some detail inthe drawings and foregoing description, they Iare to be considered asillustrative and not restrictive in character, as other modificationsmay readily suggest themselves to persons skilled in this art and withinthe broad'scope of 4the invention, reference being had to the appended,claims. Y,

The invention claimed is:

l. A roof ventilator air discharge assembly adapted to be mounted on apreconstruoted, vertically-extending curb structure, said assemblyincluding a tubular, rectangular frame member supported by said curbystructure and pivotally Secured thereto along a pivotal support axisparallel to one of 'its sides, the upper portion of said frame mem-berbeing formed to provide ya. circular air inlet aperture disposed abovesaid curb structure, a concavo-convex hood disposed -in spaced,overlying relation to said inlety aperture with its concave side facingsaid aperture, means extending between said frame member and themarginal area of said hood for supporting said hood, a verticallypositioned shaft mounted for rotation within said hood and having aportion extending beyond the convex outer face thereof, an air-movingimpeller mounted within said hood and driven Iby said shaft, saidimpeller being positioned coaxially with said inlet aperture for drawingair through said aperture and discharging it through the space boundedby said hood, spaced L- shaped members having their ends attachedrespectively to the `outer face of said hood adjacent its central axisand adjacent its peripheral margin whereby one set of legs of saidL-shaped members extend substantially vertically and the other sethorizontally, motor support means carried by the vertically extendinglegs of said L-shaped members, a motor carried by said support means anddisposed so that its shaft extends vertically, power transmission meansextending from said motor radially across the upper surface of said hoodto said extending shaft portion for driving said shaft, and a cover forsaid motor and transmission means removably supported 0n said hood, saidmotor being disposed outboard of the pivotal support axis of said framemember whereby as said frame member is tilted about said pivotal supportaxis said motor acts as a counterweight.

2. A. roof ventilator assembly as claimed claim l wherein said motorsupport means includes two plates hingedly joined to each other, one ofsaid plates being rigidly supported on said L-shaped members and theother being rigidly attached to said motor, and resilient meansextending between said plates urging them apart, whereby said motor isurged away from said hood. y

3. A roof ventilator air discharge assembly adapted to be mounted on apreconstructed, vertically-extending curb structure, said assemblyincluding a tubular, rectangular frame member supported by said curbstructure and removable therefrom, the upper portion of said framemember being formed to provide a circular inlet aperture disposed abovesaid curb structure, a concavo-convex hood disposed in spaced, overlyingrelation to said inlet aperture with its concave side facing saidaperture and supported by said frame member, a vertically positionedshaft mounted for rotation within said hood and having a portionextending beyond the convex outer face thereof, an air-moving impellermounted for rotation within said hood and driven by said shaft, saidimpeller being positioned coaxially with said inlet aperture for drawingair through said aperture and discharging it through the space boundedby said hood, an L-shaped support member having its ends attachedrespectively to the outer surface of said hood adjacent its central axisand adjacent its peripheral margin whereby one leg of said supportmember extends substantially vertically and the other leg horizontally,motor support means carried by the vertically extending leg of saidsupport member, a motor carried by said motor support means and disposedso that its shaft extends vertically, power transmission means extendingfrom said motor radially across the exterior upper surface of said hoodto said extending shaft portion for driving said shaft, and a cover forsaid motor and transmission means removably supported on said hood, saidmotor being disposed outboard of the line or" juncture of said framemember and said curb structure whereby said frame member may be tiltedabout the frame and curb line of juncture closest to said motor, suchtilting being facilitated by the weight of the motor acting as a counterweight.

LVA roof ventilator assembly as claimed in claim 3 wherein said motorsupport means includes two plates hingedly joined to each other, one ofsaid plates being igidly supported on said support member and the otherbeing rigidly attached to said motor, and resilient means extendingbetween said plates urging them apart, whereby said motor is urged awayfrom said hood.

5. A roof ventilator discharge assembly adapted to be mounted on apreconstructed, vertically extending curb structure, said assemblyincluding a frame member whose upper portion is formed to provide an airinlet aperture, a concave-convex hood disposed in spaced overlyingrelation to said inlet aperture with its concave side facing saidaperture, a shaft and a supporting bearing structure for the shaftextending through the apex of said hood and suspended therefrom, an airmoving impeller carried by the shaft and disposed within said hood, adrive motor supported exteriorly of said hood and substantially belowthe hood apex, and motion transmission means extending between saidshaft and said motor exteriorly of said hood.

6. A roof ventilator as claimed in claim 5 wherein said impeller shaftand bearing assembly are detachable with relation to the hood from theexterior thereof, thereby permitting said shaft and bearing assembly tobe withdrawn from the hood after said impeller is loosened on saidshaft.

References Cited in the le of this patent UNITED STATES PATENTS1,694,868 Sawyer Dec. 11, 1928 2,483,377 Young Sept. 27, 1949 2,582,902Gohl Ian. 15, 1952 2,735,611 McLean Feb. 2l, 1956 2,875,678 ShepherdMar. 3, 1959

